Cellular mechanisms in ocular immunologically mediated disease are being studied in animal models of experimental autoimmune uveoretinitis (EAU). Rats and mice are immunized with retinal-derived antigens or synthetic peptides representing fragments of these antigens to induce EAU. Susceptibility to disease induction is being evaluated in various strains of known genetic makeup, in the hope of delineating the hereditary mechanisms that predispose to uveitis. EAU in rats and mice serves as a template for the evaluation of new drugs and compounds, as well as for the study and characterization of the participating cells and their factors. In vivo-functional long-term T-cell lines and T-cell clones are developed from lymphoid organs of rats and mice immunized with uveitogenic ocular proteins. The functional properties and antigen receptors of these cells are studied to develop strategies for in vivo targeting of the autoimmune cells. The goals of these studies are to identify the immunogenetic factors predisposing to uveitic disease, to learn about the pathogenic mechanisms involved, to characterize the immunoreactive cells and their mediators, and finally to use this knowledge for designing rational approaches to immunotherapy.